"Those of us in Washington are not serving the people as well as we should," he said. "At times, it seems like we're unable to listen to one another; to have at once a serious and civil debate."

Obama contrasted the sense of duty and service summoned in response to disasters such as the earthquake in Haiti with the seeming inability of the nation's policymakers to respond to "the slow-moving tragedies of children without food and men without shelter and families without health care."

The president bemoaned a political culture in which disagreement on policy quickly morphs into questioning one another's motives. Obama, a Christian who was born in Hawaii, alluded to the undercurrent of assertions that he is a Muslim who was born outside the United States, saying, "Surely you can question my policies without questioning my faith or, for that matter, my citizenship."

Speaking at the Hilton Washington hotel to an audience that included Vice President Biden, congressional leaders, Secretary of State Hillary Rodham Clinton and an array of religious leaders and foreign dignitaries, Obama called on the group to step outside its comfort zone to bridge divisions and unite around common goals.

The prayer breakfast has been held in Washington for more than half a century, and every president since Dwight D. Eisenhower has taken part. The watchdog group Citizens for Responsibility and Ethics in Washington had written a letter asking Obama to boycott the event, saying its sponsor, the Fellowship Foundation, is a "shadowy religious association" that preaches "an unconventional brand of Christianity." It also said the group is linked to efforts by Uganda's political leadership to pass anti-gay legislation, including the death penalty for HIV-infected people convicted of having sex with someone of the same gender.

But Obama chose to attend the breakfast at a time when he has called on Congress to be more open in debating the merits of competing policy ideas.

Much of his domestic agenda is snared in a web of GOP opposition in Congress. The recent victory of Republican Scott Brown in a special Senate election in Massachusetts deprived Democrats of a filibuster-proof majority in that chamber.

In his address, the president renewed his call for lawmakers to seek common ground.

"We may disagree about the best way to reform our health-care system, but surely we can agree that no one ought to go broke when they get sick in the richest nation on Earth," Obama said. "We can take different approaches to ending inequality, but surely we can agree on the need to lift our children out of ignorance; to lift our neighbors from poverty. We may disagree about gay marriage, but surely we can agree that it is unconscionable to target gays and lesbians for who they are -- whether it's here in the United States or . . . more extremely in odious laws that are being proposed, most recently in Uganda."